The explosive was planted underneath a car in the Jamrud area, two kilometres (1.2 miles) northeast of Landi Kotal, the main town of the Khyber tribal region, in northwest Pakistan.
"The explosion killed two people and wounded five others," a senior local administration official Muhammad Jameel Khan told AFP, adding that nobody so far had claimed responsibility for the blast.
Another local official, Ismat Ullah, also confirmed the incident and casualties.
Khyber is home to Taliban insurgents and militants from extremist group Lashkar-e-Islam, which means Army of Islam, led by local warlord Mangal Bagh.
The district neighbours the northwestern city of Peshawar, which is increasingly the target of Taliban and Al-Qaeda-linked bomb attacks.
US officials consider northwest Pakistan a haven for Al-Qaeda and Taliban militants who fled the 2001 US-led invasion of Afghanistan to regroup and launch attacks on foreign troops across the border.
Pakistan has launched several operations in the past two years in Khyber to flush out the fighters. (*)
Editor: Kunto Wibisono
Copyright © ANTARA 2012